热风炉距离入风井口不少于()米。
A.20米
B.30米
C.50米
参考答案:A
Limited natural resources should be made full use of _______ the _______ need of energy.
A.meeting; increasing
B.to meet; increased
C.meeting; increased
D.to meet; increasing
在()时不允许用隔离开关直接拉合避雷器。
A.雨雪
B.冰雪
C.雷电